Posted
by
samzenpus
on Wednesday August 15, 2007 @02:15PM
from the read-all-about-it dept.

Michael J. Ross writes "One of the most powerful and popular content management systems (CMSs) is Joomla, a superior derivative of Mambo. Out of the box, Joomla makes it relatively easy to build Web sites that allow collaborative editing of content, attractive styling via prebuilt templates, and many more features. A Joomla-based site can be further improved by adding custom modules, components, and other extensions to the CMS, without any modification to the core Joomla code. A resource that explains how to do this, is Learning Joomla! 1.5 Extension Development: Creating Modules, Components, and Plugins with PHP, by Joseph L. LeBlanc." Read on for the rest of Michael's review.

Learning Joomla! 1.5 Extension Development

author

Joseph L. LeBlanc

pages

176

publisher

Packt Publishing

rating

8

reviewer

Michael J. Ross

ISBN

1847191304

summary

A practical tutorial for creating Joomla! 1.5 extensions

The book is put out by Packt Publishing, under the ISBNs 1847191304 and 978-1-847191-30-4. The publisher maintains a page on their site dedicated to the book, where visitors can read summaries of the chapters and the overall book, order the e-book version (in PDF format) at a discount, download the book's sample source code, read and submit errata and feedback, and download a sample chapter, namely, "Chapter 1: Joomla! Extension Development: An Overview" (also in PDF format). Note that, as of this writing, the errata and feedback do not have their own links, but are located on the page accessible via the link "Code download," which should be clarified.

The book's title page bills it as "A practical tutorial for creating your first Joomla! 1.5 extensions with PHP," and that is exactly what the book is. Rather than organizing the information in a cookbook style — which is quite popular in programming books nowadays — this particular one uses a narrative approach, in which the author illustrates the concepts by stepping the reader through an example project. He begins with a clean install of Joomla, without any of the sample data, and shows how to "build extensions to create, find, promote, and cross-link restaurant reviews."

The nine chapters of the book are organized in a logical manner, and in the order that the typical developer would go about extending a Joomla-based site: overview; Joomla's component structure and registration; backend and front-end development; module development; using the model-view-controller design pattern (MVC); creating plug-ins; adding configurability for the extensions that you have created; packaging the extension elements for use by other Joomla developers.

In explaining the key concepts and procedures for building custom extensions to a Joomla site, the author takes a methodical approach, with a healthy balance between exposition, sample code, and illustrative figures. The chapters read quickly, and the code changes from one section to the next are helpfully bolded. The chapter summaries, as with most programming books, add no value, and could be beneficially dropped, thereby saving space.

The author states in the first chapter that there are three types of extensions within Joomla: components, modules, and plug-ins. This could be confusing to anyone who has read the articles that help introduce Joomla to the new developer, and are contained in the sample data found in Joomla version 1.5. Those articles include one titled "Extensions," which lists two additional extension types — templates and languages — not considered such by LeBlanc. However, that article does not make clear as to why templates and languages should even be considered extensions, which seems counterintuitive at first glance.

The presentation of all of the material in LeBlanc's book is not perfect, but it is certainly more than adequate. It is unfortunate that the book does not have a lay-flat binding, which tends to be more of a problem with slender volumes such as this one (176 pages), since much thicker books have more weight to keep both sides down on the table at the same time when the book is open. All of the screenshots have a bit too much pixelation, which makes the smallest text within the screenshots more difficult to read. However, none of that text is unreadable. The book's text outside of the screenshots is quite easy to read, with a generously-sized font and a logical layout of each page's material. Almost every page has two horizontal lines, one at the top, and one at the bottom; they serve no purpose, and could be eliminated to save ink and space, as could the brackets around every page number. The same is true for the much larger and thicker brackets used to delineate warnings, notes, tips, and tricks. There were a few other very minor flaws in the book. For instance, in the information about the reviewer, "MySQL" is misspelled. In the Table of Contents, the "Available Toolbar Buttons" line appears to be one font size too small, and thus inconsistent with the other subsection heads. All of these weaknesses are of little consequence and could be fixed in the next edition.

Even if a reader initially had no interest in developing their own extensions to Joomla, this book could easily spark their interest, given that the book shows just how powerful those extensions can be, as well as how doable they are, by any competent programmer familiar with PHP and MySQL. In fact, even if the reader were to later decide that they had no interest in creating any extensions, they could still benefit from the book's discussion of how components are structured within Joomla — a more clear explanation than anything I have seen in the official Joomla documentation. Joomla may be an excellent CMS, but the documentation quality does not come close to the value of Joomla itself. That is why there is such a great need for books such as this one.

Although Learning Joomla! 1.5 Extension Development: Creating Modules, Components, and Plugins with PHP has some weaknesses — as do most if not all technical books nowadays — for any developer interested in getting the most out of Joomla by building custom extensions, LeBlanc's contribution should prove especially informative and useful.

Compared to the Americans, I think Canadians have it good. Let's go down the US checklist:
1) Start pointless wars with other countries costing billions of dollars, and ensuring that the people of those places are able to pass more hate for them on to the next generation. Pass that war effort cost on to the taxpayers!
2) Privatized medical system, making it so HMOs can deny you care and bill you on the silliest of claims.
3) A president so bent on his own acquisition of wealth that he's willing to sacri

Just to make it clear to any idiot mods who might attempt to give the parent a +1 Insightful/Interesting, Saskatchewan doesn't include an exclamation point in it's name. That's merely a marketing gimmick on their provincial website (and trust me, Saskatchewan can use all the marketing gimmicks it can get;).

I've used Typo3, Joomla, and Drupal. I would say that Joomla is the easiest to set up and use, but it also less customizable (although it seems to have more e-commerce plugins than some of the others). If it does what you need it to, Joomla is great. I haven't used PHP-Nuke in years but my impression is that (again) Joomla is superior in ease of use and inferior in flexibility.

The CMS Matrix [cmsmatrix.org] has a summary of features (which can be compared against other CMS systems in its list).

Joomla's admin controls definitely look slick, but I quickly noticed the inflexibility, too. Also, its lack of support for granular privileges was one of the things that turned me off of it. I think there's an extension, but I prefer Drupal's built-in support.

Thanks for the link to the CMS Matrix site. I'd been looking for something like this.

I was going to play around with Joomla! and SMF, but the bridge had been discontinued.

For those who wonder why we have had to come to such a decision, we have had input from both the Joomla! project and the FSF directly, and it is the stance of both Joomla! and the FSF that the use of a bridge into a GPL-licensed system constitutes the creation of a combined work. This forced us to reconsider our development of

I've used all three 'nuke, drupal and joomla. We started migrating sites from nuke 3 or 4 years back as we found nuke was lax on security issues and one site in particular was hacked 3 or 4 times in as many months. Personally I'm not such a great fan of Drupal, the majority of drupal sites have a very generic feel and tends to take a lot of extra work to get something that looks nice (especially if you're wanting a forum) in saying that it's a pretty solid cms, easily customisable and we didn't run into the

I'm a pretty big fan of Drupal myself (the only thing I've got against it is I don't care for PHP much), but I've got to agree with you that the Drupal forum module, while basically functional, is really ugly.

I like SMF [simplemachines.org] for a forum app, and there is a pretty good SMF bridge Drupal module [vgb.org.ru] that handles user synchronization between the two, and gives you few nifty blocks for showing recent posts and other SMF information in Drupal sidebars. It's worked pretty well for me in a couple projects.

Yeah I really like SMF as a forum app. Personally it's more intuitive to admin and seems as easy for jo public to use as say PHPBB. I can't say I've played around with the SMF Drupal bridge module - the last time I looked at it, the module was very buggy and hard to use. It's good to hear they've ironed they issues out.

I've switched a couple of forums from PHPBB to SMF and haven't had many complaints from people using the site apart from the "it doesn't look like phpbb" type of complaint

I haven't used Joomla!, but I'm absolutely in love with Drupal. It's very easy to administer (if you're at least a little tech-savvy) and has modules available for just about anything [drupal.org] you might ask of it.

For example, at my personal site [honeypot.net], I have a personalized home page [honeypot.net] with all the content I would normally have on iGoogle or My Yahoo!. If you were actually logged in as me, that page would also have my stock quotes and weather information.

I liked it well enough to convert most sites I host to it (and it has great support for virtual hosting) because I found that I was spending more time managing the management system than the content in my old setups, where Drupal just gets out of the way and makes it easy maintain. Again, I love it.

Oh, and there are plenty of nice themes floating around. I really don't like the ones that come with it any more than some of the other posts, but it's easy enough to drop in another.

I checked out Drupal and Mambo/Joomla for a large site I setup and went with Drupal. Joomla's URL aliasing setup was awful compared to Drupal. It makes sense since Mambo (on which Joomla is based) originally only supported it as a commercial add-on created by one of its core developers. With Drupal, friendly URLs were built in from the beginning.Basically, Joomla is easier to setup and add modules... but nowhere near as customizable or as extensible as Drupal. If you don't mind doing a little bit more l

Well if we are talking about product names...
Longhorn is a codename.
SAP and Oracle are company names, and products inherit from that.
Access makes sense. Think about it.
Vista, Silverlight, Excel, Delphi - OK maybe you have a point. Vista conjures up certain thoughts and feelings (or it is supposed to). Not sure about silverlight or Delphi (but wasn't there an oracle at the last one?:P). Excel? Well maybe people who use it, excel at what they do:P

I'd used to think it was a clever name, but given that it invariably comes up in these "Why does every open-source project have such a stupid name?" "Oh yeah, what does 'Excel' have to do with spreadsheets?" arguments, the pun seems to be lost on pretty much everyone.

That said, one doesn't have insist that software be named something like "Content Management System" to agree that "Joomla!" is a

Point of trivia: the Longhorn Saloon and Grill is the name of the bar that used to be (or still is, haven't worked there in 18 years) at the base of Whistler [wikipedia.org] and Blackcomb [wikipedia.org]. The bar is right between the two mountains, so it's a pretty good pun... though it implies that Vista was conceived and coded under the influence.

It's still there, I was definitely inebriated at TELUS yelling at Rahzel from their outside seating this April. It's a great spot to find, visit the Village before the 2010 games blow everything wide open.

Sort of: the company that originally produced the Oracle RDBMS was named "Software Development Laboratories", and then "Relational Software", before ultimately renaming itself after its flagship product.

Longhorn may be a codename but Microsoft used it in public a lot. To me a codename should only be used internally."SAP and Oracle are company names, and products inherit from that." Actually Oracle was the product name the company changed it's name to that of it's flagship product. It is a Greek mythology reference so I put that high up on the geek scale.

Access is just annoying since it is the second Microsoft product to use that name. The first was a terminal emulator.And yes there was an Oracle at Delphi.

Well, if you insist...-> SilverlightThat's a very visual name so to speak, inspiring thoughts of majesty and beuty, isn't silverlight a visually oriented tech?./sarcasm --on-> OracleHmm, getting information. Nope, don't see what that has to do with oracles...

-> AccessData accession, and access... Nope, don't see a pater there either

"-> SilverlightThat's a very visual name so to speak, inspiring thoughts of majesty and beuty, isn't silverlight a visually oriented tech? "Please it sounds like an super hero. "Hey Sliverlight you and Yellowjacket go cover the bank while Dr. Magic and I take care of the super tanker.""-> OracleHmm, getting information. Nope, don't see what that has to do with oracles..."Greek mytholgy reference? Yea that isn't geeky.

"-> AccessData accession, and access... Nope, don't see a pater there either".Yea

Criticism about Joomla's name makes sense, but criticism about Feisty doesn't really...Most projects have a distinctive name that is wildly different from the actual market name. Here you might see someone talking about "Feisty Fawn" (Ubuntu 7.4) or "Longhorn" (Windows Vista) or "Moonshine" (Fedora 7) but you won't see any of those products marketed by anything other than their actual brand name.

Here you might see someone talking about "Feisty Fawn" (Ubuntu 7.4) or "Longhorn" (Windows Vista) or "Moonshine" (Fedora 7) but you won't see any of those products marketed by anything other than their actual brand name.

IIRC the name "Joomla" roughly means "community" in I think Swahili. This was chosen at the point when Joomla forked from Mambo due to issues over the formation of a for-profit foundation to commercialise Mambo. The main developers thought that this was diverging away from community feel of the project and so the name they gave to the fork reflected this sentiment: that they really care about the community.

Aw, come on, do you have a dog? If so, what did you name him (or her)? "Dog?"

I feel sorry for your kids.

"Hi there, little girl, what's your name?"

"Daughter."

If you owned an automobile company, we'd be driving Cars that come in imaginative models like the Red Car and the Gray Car.

Point is, hardly anything is simply given a descriptive name of what it is. It's boooring. These days in the age of "Cingular" and "Accenture" [rpi.edu], it's the rare exception that they are. Good or bad, it's the way it is.

Informative titles are one of the most basic usability principles. Any programmer who can't grasp something this basic is probably going to have a lot of other usability issues with their software.

Case in point, we have a product named "Joomla". The Joomla administration has links to sections ambigously titled "Modules" and "Components". What's the difference between the two? Don't they refer to the same thing? And "mambots"--need I say more?

Yeah, hear hear. I used Joomla for a bit, and components, modules, and mambots don't make any sense, nor does the name have anything to do with their function. Freaking annoying as hell. Stupid geeks, they're usually so exact when it comes to naming things. Why are these programmers such idiots when it comes to creating a meaningful and consise name?

I tried using Mambo before and it was so difficult to customize. You have to be specially trained to understand the framework.
I hope this new thing is different. It's not that I don't appreciate a free and useful tool... it's just that when they expect you to learn a whole new language to do anything with it that isn't out-of-the-box is when I get peeved. Then you either have to pay for expensive training (with cash or time or both) or hire someone at crazy rates who already has the specialized knowledge

>Out of the box, Joomla makes it relatively easy to build Web sites that allow collaborative editing of content, attractive styling via prebuilt templates, and many more features.

I.E.

Makes it relatively easy to put together a website that allows lots of attackers to inject their data into the system, exploiting vulnerabilities you are completely unaware of, embedded in the guts of a multi megabyte codebase you downloaded and threw into cgi-bin.

Second (upto fiftyfiving) that. I run tons of Joomla sites, and most of them are unproblematic. As soon as the hackers gets started, though, things start to get seriously smelly. One of my sites gets SQL injected at least once a day. I did everything google, joomla.org and other resources told me about patching Joomla, but I still get 'em.
I don't regret switching to Ruby on Rails.

Who hasn't? I'd dare to say you're less likely to get SQL injections on a Rails app than on a Joomla installation, though. Rails is also pretty young. Perhaps it'd be equally common for rails app to get injected if you saw Rails apps as often as you saw Joomla installations, though. And, of course, a not-so-advanced rails developer might think that this - SomeModel.find(:all,:conditions => "foo = #{params[:bar]}") - is a good idea, and screw every effort the Rails framework made to prevent injections.

There was a Slashdot article about one of the PHP core developer guys quitting in disgust (paraphrased) due to the lack of concern for keeping it secured. When the people that wrote the stuff in the first place say it's insecure, it's insecure as far as I am concerned.Search "PHP security" for several sites that lay it out in detail, including the "Month of PHP bugs blog". Same with Joomla, people wondering about the lack of easy security in the product are not hard to find.

"I always tell them "until the fundamental security flaws of PHP and CMS in general are fixed, that crap is not getting put on a web server I am responsible for running."

Wow, I would so not hire you to run my web servers;) Neither would Yahoo, Flickr, Digg, or about 10 million other companies using php and/or CMS. How do you find work? Displaying static html pages for Amish people?

For What It's Worth, I've never used Joomla, but I do have a few Drupal sites. Druapl definitely takes the security of the platform seriously, and they fix up vulnerabilities quickly.Over the security mailing list, I haven't seen an SQL injection attack in as long a I can remember. Lately, it's all been XSS. Anyhow, they're good about getting the word out to Drupal admins whenever anything is discovered in Drupal core or contributed modules.

Yes, I've done my share of PHP. It can go in cgi-bin as much as it can go anywhere else.

If computer security is your profession (as it is mine) then you might be aware that a not uncommon technique is to configure the web server to disallow the execution of any code, including PHP, outside of a specific place such as cgi-bin. Thus reducing the attackable footprint.

There were a few other very minor flaws in the book. For instance, in the information about the reviewer, "MySQL" is misspelled. In the Table of Contents, the "Available Toolbar Buttons" line appears to be one font size too small, and thus inconsistent with the other subsection heads. All of these weaknesses are of little consequence and could be fixed in the next edition.

These are problems, but jeez -- why mention them in a book review? And he left out whether or not the colors in the logo were 100% ac

Take, for example, the impending release of Joomla 2.0 which is based on MVC architecture and will not only completely negate the value of this book, but will also likely (if it is in keeping with the Mambo developers' release history) completely invalidate any and all current components/extensions requiring everyone start from the ground, up. Again.

Even if a reader initially had no interest in developing their own extensions to Joomla, this book could easily spark their interest, given that the book shows just how powerful those extensions can be

Oh, completely. I started writing i18n add-ons for Zope and Plone the same way. I was on the BART train, heading to Oakland to catch an A's game, and I wanted something to read, so I looked under the seat and the Zope book was there. I had absolutely no interest in Python-based content management systems -- seriously, I didn't even have a Web site -- but I scraped the gum off the front cover and started reading anyway, and after a few stops I was hooked. I ended up taking the book into the Coliseum with me and had my first ZPT code written before the 4th inning.

Right! I had a similar thing happen to me! I was on my way to JavaOne, also taking BART, when I started reading about the BALCO scandal. I had absolutely no interest in baseball -- I had never even played little league, but I started reading and after a few stops I was hooked. I ended up going to the A's game that afternoon, and by the 4th inning, they brought me in as middle relief.

Also, right! Similar thing happened to me; I was on the BART and started reading this thread on my PDA. I had absolutely no interest in replying, I rarely reply to/. threads in the first place. But after a few threads I was hooked. I ended up losing my job because I spent to much time trying to come up with funny replies and in a few weeks, CmdrTaco showed up and offered me a moderator job.

Reminds me of that scene in "Blazing Saddles" in the town meeting where everyone agrees with the preceeding spe

Joomla! 1.0 was exactly the same as Mambo (just look at the code and you'll see). On the other hand, Joomla! 1.5 has been completely rewritten from the ground up. It's coding styles and structure remind me a lot of Java for some reason... must be the whole JClass naming convention. However, they have adapted the MVC pattern to every aspect of the CMS now that it has made creating components and modules (with the new structure) quite more complex. The nice part of it though is that you can separate the

Any content management system that needs to replace wholesale the main content capability to be able to categorise content in more than one category (or more than two levels of categorisation) is fatally flawed. I was assigned to a project in Joomla and within a week was begging (successfully) to use anything else - WordPress, Drupal, anything.

Very happy with Drupal now. The default install is bare-bones, by design, but you can duplicate all the Joomla functionality with a few of the modules on drupal.org and you're up and running, without the absurd restrictions, underpowered plugin hooks (something like nine in 1.x?) and godawful ugly outputted code.

Spring, Struts, Ruby on Rails, AJAX, JavaServer Faces and on and on. I'm starting to feel framework fatigue. Yet another book, on yet another framework. Before you've even mastered the current frameworks, there's another one. Sorry, I'm suffering from framework fatigue.